Introduction
It used to be that if you wanted the best sound out of your system, you started by tuning your room, which usually meant having large, cloth-covered panels along your front, back and side walls and a host of bass traps nestled in the all of the corners. If you were really crazy, you’d turn your attention to the ceiling and floor, creating a listening space that looked anything other than sexy or modern. While there is no faking good room treatments, especially on the first order reflections (in front of and to the left and right of your main speakers, as well as on the ceiling), apart from sneaking a bass trap or two into your room, the trend is increasingly moving toward using room correction software in an AV preamp or receiver to attempt to solve your acoustic issues and tune your speaker system to the audio needs of your room. But make no mistake – not all digital equalizers and room correction software are created equal. While a $500 receiver might now offer what looks to be a happening EQ system, it likely isn’t the best solution for a more demanding, audiophile-grade music and home theater playback system.

It is toward the high end of room correction where products such as the Neptune EQ find their niche. The Neptune EQ system is a fully automated, 30-band per channel equalizer, designed for the diehard home theater and multi-channel enthusiast. For a little under four grand ($3,995), the Neptune EQ features an attractive steel casing with a brushed aluminum front panel, complete with a vacuum fluorescent display that glows a pale blue and a manual directional keypad that is your only window to the Neptune’s stellar interface. The unit is roughly the size of a reference-grade DVD player and weighs about the same. The front panel features one very cool element missing from the competition: the inclusion of a front-mounted microphone jack. Most separate EQ systems – Audyssey comes instantly to mind – have the all-too-important microphone jack located on the rear of the unit, making it a bear to recalibrate if you have a custom-installed or rack-mounted system. Speaking of the back panel, the Neptune EQ has both balanced and unbalanced inputs and outputs, which are hugely beneficial, since some amps and/or systems sound better in a balanced configuration. Again, most of the competition can only be had with either/or, which makes the Neptune EQ a good value proposition. Speaking of value, the Neptune EQ also comes equipped with a calibrated microphone and stand, which no other automated, standalone EQ on the market today can claim. (The UFO-shaped mic that came with your receiver doesn’t count.) The Neptune EQ has a removable power cord, but no power button or RS-232 support of any kind. With a system as robust and complex as mine, the absence of a power switch and RS-232 support proved to be the Neptune EQ’s most glaring weakness as a new product in the high-end home theater world.

Under the hood, the Neptune EQ utilizes the latest in digital DSP technology to analyze and compensate for room anomalies across all 210 of its full-range bands. Each of the Neptune EQ’s bands can be adjusted in 1/2 dB steps at a time which provides ample amounts of control for the most diehard tweaker, or even a professional acoustician. However, tweaking a product such as the Neptune EQ somewhat defeats its purpose as a fully automated solution, but nevertheless, should you want to tune the factory presets, you can do it to your heart’s content and you’ll still be good. On top of the 30-band control, the Neptune EQ utilizes an additional 20 bands solely for the subwoofer channel, which can be the trickiest of speakers to integrate into any high-end system. Each of the Neptune’s bands is sampled at 96 kHz at 24 bits via high-end stereo codecs from Cirrus Logic. The Neptune uses separate power supplies for both its analog and digital sections for better isolation and sound quality. No receiver I have ever seen includes this audiophile feature.
All this technical talk sounds good on paper, but if the system doesn’t work as advertised and/or sounds like crap, it’s all a bunch of hot air, which is a category that describes many EQs.

Set-up
Neptune Audio’s website claims that the entire calibration process (once properly installed) can be completed in as little as four minutes, utilizing five listening positions. Being a person who loves to call “bullshit” on pompous claims, I set my stopwatch. Not rushing, and doing everything by the book, I was able to run the Neptune EQ through its paces, using five unique listening positions, in under four minutes. While I ultimately didn’t care if the process took four minutes or ten, the ease and speed with which the Neptune EQ gets you closer to musical nirvana cannot be denied.

Backing up a bit, installing the Neptune EQ into a high-end home theater went something like this. I placed the Neptune EQ between my reference Integra DTC 9.8 processor (with the built-in Audyssey room correction of course disabled) and my Bel Canto REF1000 monoblock amplifiers. I utilized all balanced interconnects from UltraLink for this particular review. Making the requisite connections was a snap. Once all interconnects and speaker cables were connected, I plugged in the Neptune EQ. Remember, it has no power switch, so once it’s plugged in, it’s on and working. I rolled my Middle Atlantic rack back into its custom closet and grabbed the included microphone. On my way back to my rack, microphone in hand, I disabled my Outlaw Audio LFM-1 subwoofer’s internal crossover and set the volume to twelve o’clock (the standard setting for most automated EQs). I plugged the microphone into the front-mounted jack and set it in my primary listening position. I then navigated the simple onscreen menu and began the process. The Neptune EQ starts by emitting a series of signals and pulses across all seven channels, notifying you if a speaker is “missing.” In my case, two were absent, since I only have a 5.1 set-up. Once all speakers were located, it ran through the tone and pulse sequence again. When this was completed, I moved the microphone to the second listening position and repeated the process on the onscreen menu. I did this for a total of five listening positions, at which point, the Neptune EQ automatically adjusted the speaker levels, distances, delays and crossover points. It did the same for the subwoofer, as well as setting the phase, which is always a nice touch. Again, the entire process once the microphone was plugged in took just under four minutes.

Once the program is completed, the Neptune EQ automatically sets itself into a “Flat” default setting, which should provide a uniform frequency response, but as my listening tests would show, it was far from the best in terms of sound.